Furnace-wall construction



Fab. 1%, 193% R. D. FOLTZ FURNACE WALL CONSTRUCTION Filed-Sept. 16. 1926 Patented Feb. 18, 1930 RAYMOND D. FOLTZ, OF SOUTH ORANGE, NEW JERSEY, ASSIGNOR TO M. H. DETRICK PATENT OFFICE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS FURNACE-WALL cons'rn rc'rron Application filed September 16, 1-926. Serial No. 135,747.

This invention relates to the construction 10 ticulars further qualifying it to withstand high temperatures over extended perlods without critical distortion of supporting frame portions or. displacement of wall refractories.

curtailing the flexibility of the refractory structure or the facility of removal or replacement of wall refractories or wall supporting portions for purposes of repair or the like.

A further object is the provision of a novel wall refractory which is specially qualified for attaining in the structure the advantages and results above indicated. a 7

Other and further objects ofthe invention will be pointed out or indicated herein after, or will be apparent to one skilled in the art upon an understanding of the invention or its employment in practice.

In the drawing forming a part of this specification, I'illustrate one form in which the invention may be embodied in structure, but it is to be understood that this is presented 5 for purpose of illustration onlv and is not to be accorded any interpretation having the effect of limiting the claims short of the true and most comprehensive scope of the invention in the art.

In the drawing, 7 Fig. 1 is a part sectional elevational view of a portion of a furnace, same be ng taken through a part of a side wall loolnng 1n the direction of the adjoining front wall;

Fig. 2 is a perspective view of a speclal wall refractory; Fig. 3 is another perspective .view of same; Fig. 4 is a perspective view of a tile retaming member; and

.50 v Fig. 5 is a top view of a wall tile.

A further object is a construction whereby: such improvements may be effected Without In modern boiler installations, the tendency 1s toward increased sizes and high ratlngs. The resulting increase in the height of furnace walls, as exemplified particularly in installations for the burning of powdered fuel in suspension, and the high temperaturesrequire'd, subject the wall refractories to destructive influences much more acute than is the case with smaller installations which are operated at lower furnace temperatures. The high temperatures generated in a furnace result in .considerable expansion of the refractories and also a softening of the refractories in their highly heated condition. As a result, it is not feasible to build high furnace walls in the fashion most generally heretofore employed for such constructions, as the weight of the material in the walls tends to squash or deform the refractories in their softened condition. Likewise, the destructive effects from erosion, and spalling resulting from heating and cooling of refractories subjected to heavy superimposed weight, are appreciably increased. The form of furnace wall construction disclosed in my two copending applications identified above is effective to minimize these destructive influences,

and among other advantages, to provide a construct on in whlch repairs may be made easily in any portions of the refractory wall,

without requiring extensive dismantling of associated portions of the structure. In the construction referred to, the refractory wall is built in a plurality of sections, associated .both collaterally and in superimposed relationships, respective sections being supported independently of the others, so that the Weight imposed upon any of the refractories is limited, and refractories may be removed from any of the sections without necessitating the dismantling of other sections. Suitable expansion joints are provided between vertically associated sections, so that the stresses from expansion occurring in one section are not transmitted to sectionsabove or below it. The present invention pertains to a wall construction of this character and will be described with reference to the illustrative embodiment shown in the drawing.

In the arrangement illustrated, let it be understood that; the numeral designates one of a number of column members which are disposed along the furnace walls, being supported on" suitable foundations at their lower ends and tied together at various points 4 .with transverse members to form a supporting frame work for the furnace wall. Secured to the column members at suitable vertical intervals are the transverse frame mem- 10 bers 11, which may be appropriate commercial is a deflected compression arm 12 terminating in a foot12 adapted to bear against the inner face of another of the .frame members 11. At the lower terminus of the flanges 12 is a project-ing shelf 12, while the tension arm 12 and the compression arm 12 are provided with laterally projecting narrow flanges 12 The section supportin members are arranged in collateral relationship along the horizontal frame members 11, and upon each of them is disposed a stack or tier ofothe wall refractories 14, the stack having support on the shelf 12 of the section supporting member. These wall refractories are tiles provided with slots 14 which receive the flanges 12, by which the refractories are retained against movement in a horizontal direction from the section supporting member. These stacks or tiers or tiles are disposedin lateral abutment, but with spaces between adjacent vertically associated stacks. The section supporting members of adjacent vertically associated stacks are disposed in staggered relationship, so that the compression arms 12 of the upper row come between the tension arms of those in the next lower row.

The space between adjacent vertically as sociated rows of stacks is filled with shoe tile 15. These are refractories of a generally L- shape having the upright arm l5 and the transverse arm 15", and are of a length corresponding to that of the refractories 14- They are narrower than the latter, however, so that a plurality'of the shoe tile is required to complete the course width of a stack of the tiles 4. The bottom face of the transverse arm 15 is at right angles to the rear face 15 v of the upright arm 15 and the front face 15 of the latter arm is parallel to its rear face. The top surfaces of both the upright and transverse arms are parallel to the lower face of the latter. The upper corner of the transverse arm is bevelled off at 15, and toward the outer end of the transverse arm 15 and in a location corresponding to that of the slot 14* of the tile 14, the bottom face is provided with a transverse groove 15 When the' shoe tile are assembled in the structure, they rest with their lower faces on the topmost tile of one of the stacks, with the front face of the upright and 15 in alignment with the ends of the tile 14 in the stack, and the rear face of the upright arm overlapping the lowermost tile 14' of the superadjacent stack or stacks so as to form a close joint between the sections. A proper clearance is left between the upper surfaces of the shoe tile and the lower surfaces of theitile and tile supporting member of superadjacent sections, the clearance space being filled with an appropriate heat resisting compressible material 16, such as asbestos or a mixture of asbestos and fire clay, to accommodate upward expansion of the lower section without imposing theexpansion stresses upon the upper sections. Particularly in walls of considerable width,

'it is desirable to anchor the shoe tile in place at intervals, to prevent their being displaced inwardly by the cumulative expansion of the tile in the horizontal row or course. To afford this anchorage for the shoe tile, while permitting their ready removal, I provide the tile retaining members 17. These are small castings of the form illustrated in Fig. 4.

One of these tile retaining members has an anchoring portion 1'? of proper dimension to fit in the slot 14 of the uppermost tile 14:, and a ledge portion 17 b extending beyond the ends of the anchoring portion and adapted to rest on the upper face of the tile 14. The ledge portion 17 is received in the groove 15 of the shoe tile, and thereby the latter is anchored against shifting inwardly. It is not essential that these tile "retaining members be employed in each stack of tile, but they may be employed where desired, thus affording anchorage for the row or course of shoe tile at intervals.

to engage a plurality of shoe tile. In the event the clearance between superadjacent stacks is not suflicient to permit the shoe tile being fitted on to the retaining members from above, the shoe tile may be slid on to the retaining members from the ends of the latter.

In the construction ofvarious types of furnaces, it may be desirable to provide air ports through the refractory wall, as indicated at P in Fig. 1. As a means for supplying and properly controlling air for admission through these ports, air compartments are provided about the refractory wall by building up a sheathing wall 18, which is supported in sections on the frame members 11. Air is supplied to the intervening air space, under suitable control, and therein is circulated over the section supporting members with the result that the latter are safeguarded against overheating, and the air receives a certain amount of preheating before passage I prefer: to have the. ledge members of sufficient length, however,

P. The bevelled portionsof the shoe tile aiford a proper clearance between the tile and the compression members 12' to allow for an intervening circulation of air. Due to the provision of the ports P, more or less radiant heat may be projected into the air chamber. As a means for protecting the steel members '11 from this heat, and also for the purpose of subdividing the space between the walls into compartments, whereby the supply of air to ports at different levels may be controlled, suitable bricks 19 are laid upon the flanges 12 ofthe juxtaposed tension and compression arms, thus forming horizontal partitions. The dimensions and design of the section supporting members are such that these bricks 19 will be positioned to cover the frame members 11 within the air compartments, thusshielding the steel members from radiant heat projected through the port-s.

By virtue of the construction and specialized form of the shoe tile, therefore, the wall refractories are given suitable anchorage such as will prevent inward bulging of the wall from expansion under heat, and all of the refractories are retained in a flexible fashion vso thatthey may adjust themselves individually with reference to their own expansion 0 and pressures transmitted to them upwardly or laterally. This flexibility in the wall structure tends to eliminate spalling of the refractories. As the section supportingmembers are freely supported on the frame mem- 35 bers, they afford a desirable lateral mobility of the respective wall sections. Tile maybe removed from any stack by first removing one or more. ofthe unanchored shoe tile, then shifting the anchored shoe tile laterally to disengage them from the retaining members 17, withdrawing them inwardly, and then moving the tile 14 upwardly to disengage them from the flanges 12, and appropriate tile may be placed in the wall by a reversal of these operations. By removal of a number of the shoe-tile, an opening is afforded through the refractory wall for'inspection proximity to the shoe-tile allows for removal of the former through the space afforded by of the sheathing wall and the frame members. The disposal\ of the partition bricks 19 in for res ective into the furnace chamber through the ports detachable from their anchoring means to permit their removal from the wall while the group of wall refractories remain in place.

2. In a furnace wall construction, the combination with separately supported wall sections made up of refractories, of tile supported on one section and overlapping another section to close the intervening space, and tile- I retaining members removably anchoring the tile to the first mentioned section.

3. In a furnace wall construction, the combination of supporting members, groups of refractories supportedvindependently by the respective supporting members, said refractories having slots affording them anchoringengagement with the supporting members, a removable tile-retaining member engaged in one of said slots, and a tile having anchoring engagement with said tile-retaining member; whereby it is held in alignment with associated refractories.

4. A furnace wall construction comprising, in combination, wall refractories arranged in superposed independently supported sections, tile closing the spacebetween sections, andtile retaining members anchoring the tile to one section independently of the other sections and retaining said tile in overlapping association with an adjacent section.

5. In a furnace wall construction, the combination of section supporting members,

groups of wall refractories independently supported in superposed relationship on respective supporting members, av tile-retainlng member engaged with a refractory of one of saidgroups, and tile for closing the space between superposed groups, said tile having laterally opening slots movable laterally into anchorin ing mem er to anchor the tile against displacement transversely of the wall.

6. In a furnace wall construction, the vcombination of a section supporting member, wall refractories supported by and anchored to said supporting member, a tile-retaining member anchored to one of the refractories and a plurality of shoe-tile having anchoring engagement with the tile-retaining member.

engagement with the tile-retain- 7. In a furnace wall construction, the c6mbination of a section supportingmember, a plurality of refractories supported on said supporting member as an upright course and having anchoring engagement with the supporting member, a tile-retaining member having anchoring engagement w'th one of the re ractories, and a plurality of shoe tile supported on said refractory and having anchoring en'gagement with the Kile-retaining memher, said shoe tile arranged in collateral disposal-and having an aggregate width ap-' proximately equal to that of the course of refractories.

8. In a furnace wall construction, the combination with a supporting, meinber, of a slotted tile having anchoring engagement member having anchoring engagement with.

p the shoe tile and its supporting refractory.

10. A furnace Wall portion consisting of a shoe tile having an upright arm and a transverse arm arranged at right angles, the upright arm having a plane front face and a plane rear. face parallel thereto, the transverse arm being bevelled at its upper corner portionand being provided in its lower face with a slot for anchoring engagement with a retaining member.

11. A structural element for a furnace wall,

consisting of a shoe tile of refractory material, same being of generally L-shape with an upright arm and a transverse arm extending at right angles, the upright arm having a plane front face and a rear face parallel thereto, the transverse arm having a plane lower face and being provided in said'lower face with a transverse groove for engagement with a retaining member, whereby the rear face of the upright arm may be retained inas- 5 sociation with a wall portion disposed in the reentrant angle between the arms.

12. An element of furnace wall construction,

consisting of a plurality of identical shoe tile of refractory material, said shoe tile being of 40 generally L-shape, each having. an upright arm and a transverse arm extendingat right angles, both said arms having parallel lateral faces, the upright arm having parallel front a and rear faces at right angles to said lateral faces, the transverse arm having parallel top and bottom faces extending at right angles to the front face of the upright arm, the last mentioned arm having a top face extending parallel with the bottom face of the transverse arm, the transverse arms of said re- 'fractories being provided in their lower faces with grooves opening laterally of the refractories, whereby the several refractories may have anchoring engagement with a retaining member to hold the rear facesof their upright arms in alignment.

13. In a furnace wall construction, the com- ,bination. of frame members, section supports supported on said frame members, refractory 60.wal1 sections supported on the section sup- 1 ports, refractory shoe tile removably mounted between sections, a sheathing wall spaced from the refractory wall sections, and partition brick supported on the section supports between the sheathing wall and'refractory tory wall sections carried by the section supports in association to form a refractorywall,

a sheathing wall spaced from the refractory Wall to afford an intervening air chamber, and brick carried by the section supports between the sheathing wall and refractory wall in covering relationship to frame members exposed in the air chamber, to shield said exposed members from radiant heat from the refractory wall.-

15. In a furnace wall'construction, the combination of frame members, section supports mounted. thereon, refractory wall sections carried on said supports, a sheathing wall spaced from the refractory wall sections, par- 5 tition brick disposed in the space between the sheathing wall and refractory wall sections, 7 refractory shoe tile closing the space between superadjacent Wall sections, and a tile-retaining member anchoring shoe tile to a wall secv tion in position to form an abutment for partition brick. I

'16. In a furnace wall construction, the combination of frame members, section sup ports mounted thereon, refractory, wall sections carried by said supports, a sheathing wall'spaced from said refractory wall sections, partition brick subdividing the space between the sheathing wall and refractory" wall sections, refractory shoe tile disposed in association with said partition brick and closing the. space between superadjacent refractory wall sections, and a tile-retaining member anchoring the shoe tile against movement inwardly from the wall sections. a

17. In furnace wall construction, in combination, refractories anchored in separately supported superposed wall sections, shoe tile disposed in the wall between the anchored refractories of adjacent sections to form a 'por- 110.

tion of the wall therebetween and means anchoring said shoetile to, one section and permitting removal of said shoe tile horizontally from the wall while the anchored refractories remain in place, the removal of said shoe tile 115 aifording space for removal of anchored refractories from their anchorage.

18. In furnace wall construction, in combin'ation, relatively movable wall sections disposed in superposed relationship, the re- 12o spective sections comprising refractories anchored against displacement horizontally but detachable from their anchorages by upward movement, shoe tile inserted in the wall between the anchored refractories of adjacent 12*5 sections to close the space between the sections, and a tile retaining member anchoring" saidshoe tile to one of the sections to prevent horizontal displacement of the same transver sely of the wall but per'mittingmemovalone of the sections independently of the other section, and compressible material be tween the shoe tile and said other section, the

removal of said compressible material affording space for movement of the shoe tile 1 to disengage same from'said retaining means.

In testimony whereof I have hereunto subscribed my name.

RAYMOND D. FOLTZ.

v CERTIFICATE or CORRECTION.

Patent No. l, 747, 824.

Granted February 18, 1930, to

RAYMOND FOLTZ.

It is hereby-certified that error appears in theprinted specification of the above numbered patent requiring correction as follows: Page 1, line 3, for num ber "684,689" read "684,698"; page 2, line 79, for "snperadjaeent" read "superjacent page 3, line 68, claim 1 for the word "group" read "groups"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

(Seal) Signedand sealed this 15th day of April, A. D. 1930.

M. J. Moore, Acting Commissioner of Patents. 

